Hydrocephalus is a relatively common condition where cerebrospinal fluid (CSF) accumulates in the brain causing increased intracranial pressure, brain damage, and death if not treated. In the United States, hydrocephalus affects over 1,000,000 people. The standard treatment is surgery to implant a device called a shunt which is then required for the life of the patient. The shunts fail at a very high frequency (50% within 2 years, 98% within 10 years).
However, the symptoms of shunt failure are nonspecific such as headache, nausea, vomiting, and lethargy. Shunt failure is life-threatening and typically requires urgent surgery for repair or replacement. Therefore, when someone with a shunt experiences a headache or other symptoms, they are admitted to the emergency department of a hospital for testing, including CT or MRI scans. These indirect tests are adequate for detecting shunt malfunction. However, our primary research indicates that 80% of patients undergoing diagnostic tests for shunt malfunction actually have a working shunt and, thus, the symptoms were a “false alarm.”
Diagnostic testing like CT and MRI are effective to diagnose the malfunction of the shunt; however, currently there isn't a method to diagnose malfunction without these costly work-ups. A device called ShuntCheck III has tried to solve this problem by cooling an area of skin above the catheter of the shunt and measuring changes in temperature downstream. However, this method is not very sensitive and is user-dependent, resulting in inaccurate results. Other technologies like micro-electric-manufacturing-systems (MEMS) or ultrasound has been proven to be limited in its capability to detect low CSF flow over time.
Therefore, it would be desirable to have a system and method for detecting if an implanted shunt is malfunctioning to properly drain cerebrospinal fluid. Further, it would be desirable to have a system and method for detecting if an implanted shunt is malfunctioning that is non-invasive and does not require costly MRI or CT test. In addition, it would be desirable to have a system and method for detecting if an implanted shunt is malfunctioning that proactively determines if fluid is flowing through the catheter in communication with the implanted shunt. In addition, it will be desirable to measure the flow of the CSF in the shunts to characterize production and flow of the CSF.